What is Network Access Control (NAC)?

Published on: August 16, 2022

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28 min read

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For German Version

With BYOD rules, third-party or contractor agreements, and IoT devices, the number of endpoints used by an organization and its partners continues to increase. In addition, as a consequence of the larger attack surface, cybercriminals have enhanced the scope and complexity of the cyber attacks they launch against these devices. Therefore, demand for NAC solutions is on the rise.

The process of preventing unauthorized users and devices from entering a private network is called network access control. Using network access control, organizations that sometimes let specific devices or users from outside the firm's network access may guarantee that these devices comply with corporate security compliance standards.

Even though NAC is a nearly 20-year-old technology, its deployment has mostly been limited to major corporations. As the network edge continues to expand outside physical business perimeters and the COVID-19 epidemic pushes the adoption of at-home, mobile, and hybrid work environments, NAC has become an enabling technology for Zero Trust Network Access security strategies.

As networks grow more distributed and complicated, cybersecurity teams must discover methods to retain visibility over the devices connected to the organization's network's most remote locations. This functionality is provided by NAC via the detection and visibility of all devices entering the network, centralized access control, and policy enforcement across all devices.

This article covers the following topics in detail: What network access control is, how it works, types of NAC solutions, why organizations need a NAC solution, benefits, and limitations of network access control, common use cases of NAC, and key points for selecting a NAC solution, top NAC solutions available in the market; and best practices for implementing a NAC.

What Does NAC Mean?

Network Access Control (NAC), also known as network admission control, is defined by Gartner as a technology that allows businesses to create rules for managing access to corporate infrastructure by user-oriented and Internet of Things (IoT) devices. Network Access Control, or NAC, is a network security solution that provides network visibility and access management by enforcing policies on corporate network devices and users. Policies are dependent on authentication, endpoint configuration, or the role/identity of the user.

Network access control is a technique for enhancing the security, visibility, and access management of a private network. NAC limits network resource accessibility to endpoint devices and users that conform to a predefined security policy. It is a multidimensional field that encompasses access control solutions for many sorts of resources, such as traditional PCs and servers, as well as network routers and IoT devices. In addition to access control, NAC encompasses device identification, threat monitoring, and policy-based administration of access control for networked resources.

Furthermore, a NAC solution sets post-connection restrictions depending on cooperation with other security solutions. For instance, NAC may implement a policy to contain the endpoint in response to a SIEM warning.

NAC solves the security needs of both wired and wireless networks(WLANs).

What Are the Types of Network Access Control?

There are two fundamental network access control methods. Both are essential for network security:

• Pre-admission: The first sort of network access control is termed pre-admission because it occurs before network access is given when a user or endpoint device begins a request for network access. A pre-admission network control assesses the access request and only permits network access if the requesting device or user can demonstrate compliance with corporate security policy and authorization to enter the network.

• Post-admission: Post-admission network access control occurs when a user or device attempts to enter a different portion of the network. If the pre-admission network access control fails, the post-admission network access control may restrict lateral movement inside the network and reduce cyber attack damage. Upon each request to transfer to a new network segment, a user or device must re-authenticate.

The NAC is be set depending on the placement of the network's decision-making and enforcement mechanisms:

• Out-of-band NAC systems: Typically, out-of-band solutions use a policy server that is not in the direct path of network traffic. The policy server connects with network infrastructure devices, such as switches, routers, and wireless access points, which apply the NAC rules and appropriately allow or refuse traffic.

• Inline NAC systems: Inline NAC systems integrate decision-making and enforcement at a single location inside the usual traffic flow. This may require a substantial amount of resources on bigger networks, and if anything goes wrong, it has the potential to negatively impair network performance.

What Typical Use Cases Exist for Network Access Control?

NAC tools are intended to prevent unwanted access before it occurs. They safeguard the devices, physical infrastructure, apps, software, and cloud-based assets of an organization's network perimeter.

There are several use cases for network access control. The most common examples of network access control use are as follows:

1. BYOD: The exponential proliferation of mobile devices has freed workers from their workstations and enabled them to work remotely on their mobile devices. Before network access, NAC for BYOD assures compliance for all employee-owned devices.

2. Incidence Response: Third-party security components get contextual information (such as user ID or device type) from NAC suppliers. They automatically enforce security rules that isolate infected endpoints in response to cybersecurity alarms.

3. Visitors and Partners: Organizations utilize NAC solutions to ensure that contractors, guests, and partners have network access credentials distinct from those of workers. Companies have typically relied on VPNs to enable secure encrypted connections for remote access to the corporate network for totally remote workers and contractors. A VPN does not prevent an endpoint from accessing the network; it only enables distant network communication. A VPN cannot verify a user on its own; it cannot prevent "unhealthy" devices from connecting to the network. In the case of remote access, NAC may be built on top of a VPN, VDI, or other remote access techniques, to offer effective authentication, access control, and endpoint risk profiling.

4. Medical Gadgets: It is crucial to identify devices entering a converged network as the number of online medical devices rises. NAC solutions may aid in protecting devices and medical records from attacks, enhancing healthcare security, and bolstering ransomware defense.

5. Internet of Things: IoT devices in manufacturing, healthcare, and other sectors are proliferating tremendously and providing attackers with more access points into the network. NAC may decrease these risks in IoT devices by implementing specified access controls and device-specific profiling.

6. Regulatory Management: Typically, industries like banking, financial services, and healthcare are subject to several compliance laws, including HIPAA, PCI-DSS, SOX, and now GDPR. Many of these requirements include specified network security settings that demand access restrictions to prevent the compromise of sensitive personal and private information. After defining its internal network security compliance standards, a corporation must adopt a network access control solution to put them into practice and continuously analyze its compliance position.

7. Device Risk Position Evaluation: Your business network is only as secure as its most vulnerable security connection. Therefore, constant risk assessment is essential. By continuously monitoring the network, your network and security teams can thwart cyber attacks by identifying and responding to emerging threats in real-time. In a world with ever-expanding borders and an exponential rise in endpoint types, continuous risk posture assessment must work regardless of location, device type, or data transport type.

Figure 1. NAC Use Cases

What is the Importance of Network Access Control?

Network access control (NAC) offers a considerably more robust and comprehensive layer of security for expensive or sensitive assets. NAC is a crucial component of your overall security strategy for several reasons listed below:

• Automation: When the quantity and diversity of devices used by enterprises continue to grow, organizations can no longer manually check the security rules of users and their endpoints as they seek to access the network. The automated capabilities of NAC significantly improve the efficiency of verifying individuals and devices and granting access.

  NAC systems can automate the resolution of performance and network security problems. After event log correlation, certain technologies provide active replies with specified actions done in real-time.

• Compliance: What data may be gathered, retained, and shared by an organization is governed by strong government regulations and data privacy laws. Organizations lack insight into network resources, devices, and data in the absence of an adequate network control access policy. Organizations must implement an effective NAC strategy to safeguard network access and satisfy regulatory compliance obligations.

• Unauthorized Devices: It is simple to connect devices to a network, but often difficult to monitor them. Consequently, enterprises incur a significant chance of illegal devices being present on their networks.

  For instance, under the provisions of the company's BYOD policy, employees may bring personal computers or mobile phones to the office and connect them to the network without registering them. Or, an IT staff may put up devices for testing and then forget about them despite their continued operation. These resources become shadow IT devices that are linked to your network but are not controlled appropriately.

  NAC helps prevent unwanted devices from joining your network in the first place, while also detecting those that are already connected so you may remove them or ensure their security.

• Outsider Access: Large enterprises often collaborate with contractors, partners, and third-party vendors, and must sometimes provide these external stakeholders with network access. Without an appropriate NAC policy, it is very difficult to ensure that these external devices are adequately protected and do not create an attack vector for the corporate network. In addition, it is challenging to guarantee that gadgets are removed when they are no longer required.

• Data Privacy Legislation: Government agencies and business organizations have enacted more stringent restrictions and data privacy laws governing the sorts of data a company may collect and maintain. Without NAC, businesses lack insight into the sorts of network resources available and whether or not they are subject to additional compliance regulations.

  Organizations wishing to keep ahead of security risks and regulatory difficulties must build an effective NAC strategy for these and other reasons.

• Virtual Environments: IT departments that employ virtual machines as part of their data center may profit from network access control but only provided they maintain vigilance about their other security measures. Because virtual servers may move across a data center and a dynamic virtual local area network (LAN) might vary as the servers move, virtualization provides unique issues for network access control. In addition to creating unforeseen security flaws, network access control for virtual machines may make it difficult for enterprises to conform to data audit control requirements. Because typical security approaches find endpoints using their IP addresses, this is the case. Because virtual computers are mobile and dynamic, it is more difficult to safeguard them.

  In addition, virtual machines are relatively simple and quick to deploy, which means that even novice IT administrators may deploy a virtual machine without having the required network access restrictions in place. When virtual machines are revived from a rest state, a further vulnerability is triggered. If new patches were available while the server was in the rest state, they may not be implemented when the server is redeployed. Increasing numbers of enterprises are incorporating application security into their network security policies to guarantee that everything on their network is safe, right down to the application level.

• APT: Although NAC is incapable of immediately detecting and preventing APTs, it may prevent the source of the threat from connecting to the network. Some NAC systems connect with APT detection solutions, and instantly isolate compromised computers before attackers can get additional network access.

• A variety of devices: There are now hundreds of possible combinations of device type, model, and operating system version. And mobile devices in particular may be customized in an infinite number of ways due to the enormous number of installed applications. In contrast, mobile device management (MDM) and antivirus applications are often not installed on personal devices. Users often deactivate fundamental security settings or install programs that look authentic but may damage the security of the device. This might cause APT or ransomware attacks to propagate from personal devices to the enterprise network.

  All of this presents companies with the unique difficulty of allowing these devices to connect without jeopardizing network security; the more devices that connect, the higher the chance of the network being infiltrated. Criminals are increasingly targeting mobile devices, and applications with malware have become a common attack vector.

  The leading network access control systems on the market today support Google Android, Apple iOS, and Microsoft Windows. NAC systems may play a crucial role in automatically detecting devices when they join the network and granting access that does not pose a security risk. When a personal mobile device connects, for instance, it may just have access to the Internet and no company resources. The same may now be done with IoT-enabled devices, classifying them according to predefined criteria and barring or establishing a secure network area for unauthorized devices.

How Does NAC Work?

A key purpose of network access control is to restrict network access to certain users and regions of the network. Consequently, a visitor can connect to the business network, but will not have access to any internal resources. This form of security management helps an organization prevent a cyber attack in which hackers obtain access to their third-party vendor's network and launch an attack on the organization when the vendor is connected to its network.

Network access control may also prevent workers from gaining illegal access to data. Thus, an employee who needs access to the corporate intranet will not have access to sensitive customer data unless their function requires it and they have been granted access.

In addition to restraining user access, a network access control prevents access from endpoint devices that violate corporate security regulations. This guarantees that a device from outside the company cannot transmit a virus into the network. Before being permitted network access, all devices used by employees for business purposes must conform to corporate security rules.

A network access server performs several NAC-related tasks. A classic network access server is a server that conducts authentication and authorization by validating user login information. A network access server, also known as a media access gateway or remote access server, manages remote logins, creates point-to-point protocol connections, and guarantees that authorized users have access to the required resources.

A network access server may perform the following functions, among others:

• Voice over Internet Protocol: enables access to communication apps through the internet.

• Internet service provider: a company that grants authorized users access to the internet.

• Virtual private network (VPN): provides distant users with access to the network and resources of a private organization.

Additionally, a network access server may support the following:

• Network resource management is for managing and allocating network resources

• Network load balancing to disperse traffic and enhance performance and dependability

• Network user sessions to monitor users, store their data and maintain their unique state

What are the Features of a Network Access Control System?

An effective Network Access Control (NAC) solution must have the following capabilities:

• Multiple Authentication Factors (MFA): Utilizing MFA for NAC that examines a user's credentials and an enrolled device is essential for maintaining network access control in today's rapidly increasing networks. MFA must be included into your NAC, particularly for remote access.

  This strategy guarantees that security is provided on two levels: protection of the user's identity and authorisation of the device, ensuring that only controlled and secure devices are permitted access. With MFA, if a user's credentials are hacked, they are rendered worthless, and if the device is not registered with the NAC, VDI, VPN, and cloud apps cannot be accessed.

• 802.1X Authentication: Today, the standard protocol for network access control is 802.1X. When looking for a NAC solution, it is of the utmost significance that the system supports 802.1X authentication.

  With 802.1X-based access control, network administrators may reliably ban malicious devices, quarantine noncompliant endpoints, and restrict access to specific resources, whatever your internal policy requires. Because of its constant and direct communication, 802.1X remains one of the finest methods for authenticating devices, in contrast to post-scanners and other less secure authentication solutions that expose the network to vulnerabilities.

• Cloud-Delivered: Nearly every business's core administration and productivity tools have migrated to the cloud. Controlling network access is not an exception. In the last fifteen years, the underlying productivity, operational, economic, and accessibility advantages have propelled this trend.

  However, there is a significant distinction between cloud-based and cloud-delivered NAC solutions. Some NAC providers provide a cloud-based platform for managing network access, but this often involves the installation of onsite hardware.

  With a cloud-delivered strategy, you deploy everything from a RADIUS server to a certificate authority in the cloud to provide centralized authentication and permission. This allows even big, scattered enterprises to establish NAC across all of their sites in a fraction of the time required by conventional on-premise network access control systems.

• Zero-Trust Approach for Endpoints: In spite of the fact that "zero-trust" has become another overused cliche in the realm of network security, it is an effective method for isolating your network from malicious devices. With zero-trust, an organization does not automatically trust any endpoint inside or outside its perimeters.

  As the condition of a device is already known, a zero-trust network access(ZTNA) control solution may avoid the requirement for comprehensive endpoint scanning. This does not remove all attack surfaces, but it does assist in securing your network and endpoints.

• Complete Access Layer Protection: Your NAC solution must be able to handle access control across all current access levels due to the exploding size and breadth of today's networks, especially with the development of remote workforces. This has the expected wired connectors and WiFi connectivity.

  Additionally, it must be capable of managing the numerous remote access techniques used by your firm. These consist of VPNs, virtual desktop infrastructure (VDI), and more.

• Continuous Device Maintenance: When evaluating a NAC solution, it is essential to determine whether it can quickly repair devices that fall outside of corporate risk regulations and return those devices to the correct posture so that network access may be granted. Simply put, preserving the health of devices minimizes security risk. This implies that network administrators can rest easily at night.

  Real-time device repair also has a significant operational benefit: it saves time. By reducing the need for network or security managers to manually repair devices, you enable them to focus on more crucial responsibilities.

• Corrective and Preventive Actions (CAPA): It is common to engage in risky technological practices, such as introducing an untrusted USB device or forgetting to update a firewall or anti-virus. Therefore, the capacity to avoid this harmful conduct is crucial not just to reduce exposure time, but also to save valuable time for the company by immediately resolving the problem and averting a possible security breach.

• Endpoint Risk Assessment: It is essential to be able to continually analyze the danger posed by devices connecting to or attempting to connect to your network. Understanding the risk posture of endpoints, whether on-site or remote, and proactively taking action based on endpoint risk, such as quarantining, granting, or refusing access across access levels,is the most effective method for preventing network attacks.

  The threat landscape is growing, and businesses are increasingly turning to purpose-built corporate cloud apps to simplify business operations. Today, it is no longer sufficient to secure just on-premise assets; you must examine the risk posture of every device that connects to corporate resources, regardless of location.

How to Implement Network Access Control?

The whole NAC installation must be well planned. Methods vary based on the characteristics of each network, the number of IoT and third-party devices involved, the company's budget, and the choice between pre-admission, post-admission, and hybrid network security solutions. Listed below are the fundamental steps you may take to successfully install NAC:

1. Acquire information: Before installing NAC solutions, you must collect vital information on your network, connected devices, resources, and users. You must do an exhaustive assessment of each network endpoint, including servers, equipment, and more. Who is connected to what, and whose devices are they using? Is there a commercial reason for their existing degree of access? Without this information, managing identities and assigning permissions might be difficult. This collection is provided by certain NAC solutions during the first scan.

2. Manage identities: Managing identities is one of the most significant jobs throughout the implementation of NAC systems. To approve and authenticate each user, you must configure and maintain your directory systems as well as validate user IDs. This allows you to set authorization roles and provide people with network access.

3. Determine permissions and degrees of access: After your IT staff has allocated permissions to users, you may integrate permission access rights, rules, or the complete current directory system straight into your NAC solution to eliminate security holes. An ideal implementation of the concept of least privilege would restrict all users to the bare minimum network resources required to do their duties. However, the majority of big networks are not sufficiently divided to properly conform to this notion. Implementing role-based access control may be a good compromise without compromising security too much.

4. Test the configuration: The majority of NAC systems may be set in "monitor" mode, allowing the effect of rules to be evaluated prior to their real enforcement. This is a crucial step since it helps you to identify possible issues before they produce a high number of support requests. It is good practice to test your NAC rules before implementing them and whenever you make modifications.

5. Observe and adjust: Network management is not a one-time activity. As your business grows and adapts, you must monitor security operations and manage user authorization and device access privileges or automate these activities.

What Are the Advantages of Network Access Control?

The major advantages of Network Access Control(NAC) are listed below:

• Role-based Access Control: Identifying people based on their IP addresses or combinations of username and password is a far less secure method than using multi-factor authentication, which may be required of users as part of network access controls. This is one of the advantages of having network access controls.

  Managing Active Directory group membership and network share rights in a big network, as most IT administrators are aware, is often impossible and always results in excessive network permissions. The ability to centrally manage this via a NAC system may provide better control and flexibility when granting access to shared files.

  During network penetration testing, IT often identifies lax restrictions on network shares as a significant weakness. In such a situation, having NAC supplements would go a long way toward alleviating this issue. Either directly or indirectly, NAC devices give access to personally identifiable information or data that enables further enumeration of network resources. For instance, if a misconfigured IT share permitted access to passwords for many major databases, including customer names, addresses, dates of birth, and credit card information, a NAC system would limit the risk to this data.

• Increased Visibility: After a user has been granted access to a network, secure network access control may offer extra degrees of protection around certain areas of the network, therefore assuring the security of applications. Some of the methods for controlling access to a network may also incorporate suitable security features, such as encryption and greater visibility throughout the network.

• Cost Saving: Organizations incur lower costs since fewer IT personnel are required when devices are tracked and protected automatically at scale. In addition, stopping unauthorized access or a suspected malware assault saves firms from incurring financial damage, which might occur if these actions are not prevented.

• Superior IT Experience: With seamless access, the user experience during network connection is frictionless. The fact that measures are in place and operating in the background provides users with confidence that their IT experience is safeguarded automatically.

• Enhanced Security: NAC strengthens network security by authenticating people and devices at the time they join the network, owing to its ability to monitor all organization-wide devices. Malware threats and other types of cyber attacks are mitigated by the capacity to monitor network activity and take fast action against unauthorized or unexpected conduct.

What Are the Limitations of Network Access Control?

Despite these capabilities in handling authentication for users and known devices, NAC is prone to a number of additional constraints:

• Control of network access for wired networks: While access to wireless networks is often protected by protocols such as WPA, wired networks sometimes lack such safeguards. They often issue an IP address through DHCP and provide a complete connection to any plugged-in device (and if they don't, the device or user may manually establish an IP address).

  This method is handy since it removes the need to handle authentication credentials for wired devices and users. Because only people with physical access to its infrastructure are able to plug in devices, organizations mistakenly feel the security concerns are negligible. Unsecured wired networks are, nevertheless, attractive entry points for shadow IT devices into an organization's infrastructure.

• Insufficient insight into IoT and uncontrolled devices: NAC is only effective at controlling security threats for known and user-associated devices, like PCs or tablets, which is one of its key drawbacks. IoT sensors and other network-connected devices that do not have a single user or group of users linked to them are more challenging to manage with NAC. Due to hardware capacity constraints or a lack of human input, some devices may not accept conventional authentication methods or security certificates. As a consequence, companies tend to blindly accept and exempt these devices from regular NAC regulations.

• Capability to set device policies: Unmanaged, non-user devices, such as Internet of Things (IoT) hardware, may depend on specialized communication protocols that are not supported by traditional NAC authentication rules or tools. Faced with this difficulty, companies are forced to choose between exempting these devices from NAC regulations or developing very complicated policies to accommodate them. Both strategies are not optimal.

• Monitoring for hazards after entry: Due to NAC's emphasis on restricting network access, it is only effective against external threats. It does not guard against "insider" attacks that start on an already-authenticated device or identify breaches after they have occurred.

Top Network Access Control (NAC) Solutions for 2022

There are dozens of NAC solutions available on the market, but let's examine the most common NAC solution below:

• Aruba ClearPass: Aruba ClearPass is used in a number of hospitality and academic settings, often in conjunction with the company's wireless networking devices. This close interaction between hardware and software may provide real-time data about how network devices are being used.

• Cisco Identity Services Engine (ISE): Cisco was a pioneer in the network access control market and has developed a variety of solutions over the years. In addition to standard NAC technology, Cisco ISE connects with many other components of the Cisco ecosystem to provide segmentation, visibility, and automated response.

• Forescout: The Forescout Platform (consisting of eyeSight, eyeControl, eyeSegment, and eyeExtend product licenses) provides security and IT operations teams with real-time awareness of any IP-connected devices that contact the network. Users may choose from over 20 active and passive discovery and profiling techniques to meet the business context and guarantee ongoing network uptime. In the Forescout Device Cloud, more than 12 million device fingerprints provide device classification capabilities to detect device function, operating system, vendor, and model.

• FortiNAC: Fortinet is well known for its firewalls, but the business also provides a variety of network access control systems under the brand name FortiNAC. Fortinet boasts a variety of profiling methodologies, scalability to "millions of devices", and compatibility for network infrastructure components from over 150 manufacturers.

• InfoExpress: InfoExpress provides a series of devices that satisfy various NAC criteria. Without network modifications, they provide enforcement that protects access for mobile, desktop, and IoT devices. The CGX server represents the corporate version. It may be implemented as a virtual machine (VM) or appliance that delivers a comprehensive suite of network access control apps to provide a customizable and customized NAC solution.

• Ivanti Policy Secure: Formerly known as Pulse Policy Secure, this network access control solution is compatible with a variety of third-party products and provides the necessary policy management, profiling, visibility, and behavioral analytics features of a modern network access control platform.

• Portnox CLEAR: Unlike typical suppliers, Portnox offers a cloud-native NAC technology provided through software-as-a-service in addition to their on-premise solutions. Organizations that do not want to set up and operate their own remote authentication dial-in user service servers may find the integrated cloud authentication and policy server capabilities to be an interesting solution.

How to Choose a Network Access Control Product?

NAC solutions are available in several variants to accommodate various deployment types, use cases, and organization sizes. There is no "correct" or "best" answer since what works for one company may be utterly wrong for another. While researching prospective solutions, ask yourself the following questions:

• How closely does it correspond to our use cases?:

  All network access control systems strive to provide you with control over which devices may connect to your network, but support for specific use cases might differ significantly. You'll need a solution with a robust captive portal, self-registration, and segmentation features if you're searching for anything that simplifies controlling guest access. Managing IoT or BYOD situations, on the other hand, may need a system with robust device profiling and posture capabilities.

• Is it compatible with our current infrastructure?:

  To help narrow down your search, it may be useful to examine what your firm is currently using. If you've invested considerably in networking equipment from a certain manufacturer, it may be prudent to evaluate that vendor's network access control (NAC) solution to ensure everything works together flawlessly. While it is true that 802.1x is an open standard, many companies' advanced features are typically proprietary and may not be accessible in a mixed environment.

• Does it provide scalability?:

  The scalability of NAC systems varies by manufacturer and deployment type. In busy networks, for instance, inline network access control often does not scale effectively. Remember to look beyond the NAC product as a standalone solution: if you're utilizing existing network infrastructure devices to implement NAC regulations, the added overhead might be onerous on older routers, switches, and access points.

• What is the price?:

  Especially if you anticipate a big number of BYOD devices, price points, and pricing models might be significant factors to consider. Some NAC systems are paid per device or user, while others may be flat-rate. There are both perpetual and subscription license variants available. You should also consider scalability and high availability; one solution may need a higher number of policy server instances than another to accommodate a given number of endpoints.

What are the Best Practices for Network Access Control Implementation?

In this section, we will describe important things to consider before implementing a NAC solution in your organization. NAC is not appropriate for all companies. The greater the size of the company determines the number of devices that will connect to the network and, therefore, the greater the use of network access control solutions.

These best practices will assist you in maximizing network access control systems and fortifying business perimeters.

1. Combine pre-admission and post-admission network access control: There are two major classifications for network access control: pre-admission and post-admission. Together, these two methods of network access control provide a comprehensive defense against cybersecurity threats. Access is denied to unauthorized users from the outset. Before gaining access to your most sensitive data, threats that breach pre-admission security via deception must pass through an additional authentication cycle. This strategy is useful against insider assaults as well.

2. Select judiciously your network access control solution: When selecting a solution partner, you have many possibilities. Network infrastructure suppliers provide network access control as an add-on to networking solutions, enhancing the value proposition via consolidation and integration. In addition, cyber-physical security solutions and SASE are available for IoT and remote environment security, respectively. In this market environment, network access control partners must be chosen judiciously, by existing use cases and future projections:

   • Assess your endpoints and current endpoint security to pick an interoperable solution. For unified visibility, network access control must be natively integrated with your unified endpoint management solutions.
   • Align network access control implementation with any enterprise-wide zero-trust identity and access management (IAM) policy currently in effect. Network access control enables a "deny by default" strategy that strengthens zero-trust capabilities.
   • Concentrate on suppliers that cater to businesses of your size and complexity, and if feasible, your industry vertical. Ultimately, the criteria for access in a digitalized healthcare environment will be considerably different from those in a linked factory.
   • Before choosing a vendor, do an inventory of the network. In addition to revealing any unmapped endpoints, undiscovered access gateways, existing network switches, etc., this will also provide an IP volume estimate for network access control budgeting.

3. Educate IT personnel on network access control: Network access control has its own specialized terminology, and an IT generalist may not be able to use it to its full potential. Even if a vendor has exclusive or shared responsibility for network access control deployment and maintenance, your IT personnel will be required to perform day-to-day upkeep and maintenance. Additionally, the ability to evaluate network access control warnings and data patterns is a crucial skill. If network access control warnings are read and acted upon on time, major security harm caused by illegal access may be avoided. As network access control encompasses your complete on-premises device and user footprint, there will be many alarms to evaluate and analyze. Depending on the number of endpoints, you may need to appoint a network access control administrator to monitor alarms, filter out false positives, and maintain business security without disrupting processes or inconveniencing genuine users. The following are some of the essential abilities for which IT employees may need training:

   • Knowledge of cyber systems and unconventional endpoints
   • Data interpretation, analysis, and mapping of trends
   • Workflow user experience and technological dependencies
   • Integration and interoperability of security for end-to-end visibility

In addition to IT personnel, you need to notify guest users and third-party stakeholders about network access control deployment.

4. Be vigilant for use case candidates: In a digital organization, several use cases might benefit from network access control deployment, but they are typically overlooked. Consider installing network access control if any of the following situations apply to your enterprise:

   • Internet of Things: There are several linked endpoints on your premises, ranging from IP-equipped printers to biometrically enabled smart doors.
   • Bring your device regulations: Employees bring their personal computers to the office and take their work gadgets home, utilizing them interchangeably for personal and professional reasons.
   • A significant third-party ecosystem: Regularly, non-employees and third-party users are present on your business premises. Some even have network access credentials inside the organization.

5. Implement network segmentation for security after admission: Network segmentation enables dynamic and automated grouping of users and devices based on preconfigured security settings. By isolating infected or malicious assets, segmentation decreases your attack surface. There are several methods to tailor network segmentation depending on the identification of users or devices, their risk levels, the location of access requests, the time of connection, or any other business criteria. In your network environment, high-risk devices may be segregated and put in quarantine for additional approval. It is also essential to centralize your network segmentation rules so that the same standards are followed across the business and threats are met with a uniform reaction. This will assist in standardizing your security posture and ensure that no mistakes escape through the cracks between fragmented security rules, various segmentation methods, etc.

6. Deconstruct the network access control implementation procedure into reasonable stages: Initially, the network access control architecture might seem daunting due to its many components and tight interactions with the current IT infrastructure. It is crucial to divide network access control deployment into the five basic phases explained above.

7. Investigate optional integrations for more value: You may also investigate integrations with your network firewalls, security information and event management (SIEM), identity and access management (IAM), and advanced threat prevention solutions. This establishes a single line of responsibility and control, unifying your security posture into a coherent whole. As the perimeter of your company expands, network access control will become essential for maintaining insight into user and device activities on corporate and guest networks. The introduction of cloud-based network access controls is the next frontier, since it simplifies administration and opens the door to remotely controlled network access control services.

What is the Evaluation of Network Access Control?

The initial iteration of NAC is based on 802.1X protocols for the user and device authentication. If a device attempted to connect to switch ports or wireless access points, it needed to give a username/password or certificate for RADIUS server approval. This method permits or disallows access at the switch port or wireless. access point level. This strategy, although successful, is not compatible with many devices and is difficult to execute.

The second iteration of NAC included the ability to collect data through SNMP with network devices or independently with network sensor devices. In addition to 802.1X, this generation featured access control mechanisms like VLAN quarantining, ARP-based management, and port mirroring. This period also coincided with the rise of wireless networking. Visibility and control solutions such as network sensors, wireless controllers, and endpoint agents were progressively leveraged to handle developing WLAN vulnerabilities such as rogue access points.

The third iteration of the NAC included automation. Agents were able to automatically configure endpoint devices to conform to security rules, and the integration of many systems permitted the construction of a cooperative security paradigm. A security system running on the network's perimeter, such as an intrusion detection system (IDS) or firewall, may be able to identify dangers, but at most may only restrict traffic that goes through it. Integrating with a NAC allows harmful devices to be isolated from the rest of the LAN. A NAC also exchanges endpoint and user information with other security systems to improve their operation. These integrations often use standard protocols like Webhook, and Syslog.

The current generation of NAC tries to solve the challenges of diminished endpoint visibility caused by the proliferation of IoT and BYOD. This generation is characterized by an increased emphasis on enhanced device fingerprinting for managing business problems such as asset end-of-life and end-of-support, as well as automated management responses to known and new vulnerabilities. Lastly, there is a growing dependence on and integration with cloud technologies, which parallels the growing usage of cloud computing in rapidly changing networking contexts.

What is the Network Access Control Policy?

Typical network access control policies are explained below:

• Remediation Policies: In some situations, the network security team may develop a set of remedial rules. In essence, a remediation strategy comprises corrective and preventative actions (CAPA) that are automatically implemented on devices upon each transmission or regularly. A remediation strategy may be used to minimize the risk scores of devices and enhance network access compliance.

• Risk Evaluation Policies: In addition to developing an access control policy, network managers will often design a risk assessment policy that gives each device a risk score. This score will show the degree of danger the gadget poses.

  Depending on the deployed NAC solution, these risk rating methodologies may vary. A risk assessment policy specifies, for each device characteristic (such as geo-location, security posture, and operating system), the risk rating to apply if the device breaches the current policy in effect.

  The risk score is ultimately used to decide whether to allow, ban, or quarantine access to the network. This is the foundation of the NAC.

• Access Control Policies: Network security teams develop and activate access control rules to regulate device access to the corporate network, which is ultimately dependent on the authorized status of the device. A network access policy specifies which virtual LAN (VLAN) a device or user is sent to once it has been granted network access.

  In addition, the policy specifies, for each kind of permission breach, whether to refuse access, isolate the device by assigning it to a certain VLAN or apply an access control list (ACL).

  A network access control list (ACL) is a set of rules or protocols including the authorization information and access permissions of the network and network devices.

  The network ACL serves as the network's initial line of defense, ensuring that only authorized traffic enters the network. It is used to prevent network traffic from entering or leaving a single or many subnets. You may configure security rules and authorization privileges based on security groups to provide an extra layer of protection to your network.

Is a Firewall a Network Access Control?

No. By addressing various areas of network control, NAC and firewall solutions perform complementary roles. Firewall and network access control solutions exhibit the following significant distinction.

While NAC is an endpoint-centric solution, the firewall is network-centric. A firewall is often configured between two or more networks to offer access control for inter-network communication, while NAC manages communication between endpoints inside a network. For instance, NAC may regulate a file-sharing connection between two PCs on the same network, although the firewall cannot.

A firewall manages traffic by preventing non-compliant traffic from entering or leaving a network and normally operates based on basic rule sets. NAC controls network traffic between devices inside the network more flexibly by acting on the endpoints themselves.

Typically, firewall rules are created by five objects, which include source/destination addresses and ports. Recent next-generation firewalls(NGFWs) have started to control other things, such as users, groups or devices. In NAC, devices are grouped based on numerous parameters. As the behavior and qualities of a device change, so does the group it belongs to. Each group may be associated with a security policy that grants a certain amount of network permission. For instance, an endpoint that is not running an antivirus may be recognized and quarantined in real-time.